Systems And Methods For Electrodes And Coupling Structures For Electronic Weaponry

ABSTRACT

An electronic weapon with an installed deployment unit, from which at least one tethered electrode is launched, provides a stimulus current through a target to inhibit locomotion by the target. The wire tether, also called a filament, conducts the stimulus current. The one or more electrodes, according to various aspects of the present invention, perform one or more of the following functions in any combination: binding the filament to the electrode, deploying the filament from the deployment unit, coupling the electrode to the target, and distributing a current density with respect to a region of target tissue and/or a volume of target tissue. For an electrode that includes a body and a spear, the spear may be implemented with conductive rings or with materials that include integrated conductive and insulative substances (e.g., conductive fibers in insulative composite material). Relatively high electric field flux density at a tip of the spear may be reduced or avoided by practice of the invention.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of and claims priority under 35 USC §120 to U.S. patent application Ser. No. 12/979,619 to Hanchett, filedDec. 28, 2010, which is a continuation of US patent application serialno. 12/842,866 to Hanchett, filed Jul. 23, 2010, now U.S. Pat. No.8,587,918, issued Nov. 19, 2013.

FIELD OF THE INVENTION

Embodiments of the present invention relate to electronic weaponry,deployment units, and electrodes used in deployment units for electronicweaponry, and to methods of providing a current through a human oranimal target via at least one electrode having a current spreadingcapability.

BACKGROUND OF THE INVENTION

Conventional electronic weapons launch one or more electrodes toward ahuman or animal target to deliver a stimulus signal through the targetto inhibit locomotion by the target. A thin conductor called a filament(e.g., wire) couples a signal generator in the electronic weapon to alaunched electrode positioned in or near the target. The signalgenerator provides the stimulus signal through the target via thefilament, the electrode, and a return path to complete a closed circuit.The return path may be through earth and/or through a second filamentand electrode. Conventional electrodes are made of conductive materialsand have a sharp barbed tip to acquire and remain in a position in ornear a target (e.g., lodge in clothing, skin). Consequently, relativelyhigh field strengths and current densities occur at the electrode tip.Generally, reducing current at the tip of an electrode and increasingcurrent at the skin of the target is desired.

BRIEF DESCRIPTION OF THE DRAWING

Embodiments of the present invention will now be further described withreference to the drawing, wherein like designations denote likeelements, and:

FIG. 1 is a functional block diagram of an electronic weapon accordingto various aspects of the present invention;

FIG. 2 is a functional block diagram of an electrode of the electronicweapon of FIG. 1;

FIG. 3 is a cross-section diagram of an impact with target tissue of anelectrode in one implementation according to FIG. 2;

FIG. 4 is a side plan view of an implementation of the electronic weaponof FIGS. 1 and 2;

FIG. 5 is a cross-section view of the deployment unit of the electronicweapon of FIG. 4;

FIG. 6 is a cross-section of an electrode in a first implementation ofthe electrode of FIG. 2;

FIG. 7 is a cross-section of an electrode in a second implementation ofthe electrode of FIG. 2; and

FIG. 8 is a cross-section of an electrode in a third implementation ofthe electrode of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An electronic weapon, according to various aspects of the presentinvention, delivers a current through a human or animal target tointerfere with locomotion by the target. An important class ofelectronic weapons launch at least one tethered electrode, also called adart or a probe, toward a target to position the electrode in or neartarget tissue. A respective filament (e.g., wire with or withoutinsulation) extends from the electronic weapon to each electrode at thetarget, thereby tethering the electrode to the electronic weapon. One ormore electrodes may form a circuit through a target. The circuitconducts the stimulus signal. The circuit's return path may be throughground, through one or more additional tethered electrodes, or through aconductive path (e.g., liquid, plasma) formed by the electronic weaponto the target. The electronic weapon provides a stimulus signal (e.g.,current, pulses of current) through, inter alia, the filament, theelectrode, and the target to interfere with locomotion by the target.Interference includes causing involuntary contraction of skeletalmuscles to halt voluntary locomotion by the target and/or causing painto the target to motivate the target to voluntarily stop moving.

Conventional stimulus signals may be used. For example, a stimulussignal may comprise about 19 current pulses per second at a duty cycleless than 1/400, repeated for a period of from 5 to 30 seconds tofacilitate arrest of the target or escape from the target.

An electronic weapon, according to various aspects of the presentinvention, may include a launch device and one or more field replaceabledeployment units mounted to the electronic weapon. Each deployment unitmay include expendable (e.g., single use) components (e.g., tetherwires, electrodes, propellant), and storage cavities (e.g., bores,chambers). Herein, a filament is interchangeably called a wire, a tetherwire, and a tether. A tethered electrode is an assembly of a filamentand an electrode at least mechanically coupled to an end portion of thefilament. A portion of the filament near the other end of the filamentis at least mechanically coupled to the deployment unit and/or thelaunch device (e.g., one end fixed within the deployment unit),generally until the deployment unit is removed from the electronicweapon. As discussed below, mechanical coupling may facilitateelectrical coupling of the launch device and the target prior to and/orduring operation of the electronic weapon.

A launch device of an electronic weapon launches at least one tetheredelectrode of the electronic weapon toward a target. As the electrodetravels toward the target, the electrode deploys (e.g., pulls) a lengthof filament from storage within the deployment unit. The filament trailsthe electrode. After launch, the filament spans (e.g., extends, bridges,stretches) a distance from the deployment unit to the electrodegenerally positioned in or near a target.

Electronic weapons that use tethered electrodes, according to variousaspects of the present invention, include handheld devices, apparatusfixed to buildings or vehicles, and stand-alone stations. Hand-helddevices may be used in law enforcement, for example, deployed by anofficer to take custody of a target. Apparatus fixed to buildings orvehicles may be used at security checkpoints or borders, for example, tomanually or automatically acquire, track, and/or deploy electrodes tostop intruders. Stand-alone stations may be set up for area denial, forexample, as used by military operations. Conventional electronic weaponssuch as the model X26 electronic control device and Shockwave™ areadenial unit, each marketed by TASER International, Inc., may be modifiedto implement the teachings of the present invention by replacing theconventional deployment units with deployment units having electrodes asdiscussed herein.

An electrode, according to various aspects of the present invention,provides a mass for launching toward a target. The intrinsic mass of anelectrode includes a mass that is sufficient to fly, under force of apropellant, from a launch device to a target. The mass of the electrodeincludes a mass that is sufficient to deploy (e.g., pull, uncoil,unravel, draw) a filament from storage. The mass of the electrode issufficient to deploy a filament behind the electrode while the electrodeflies toward a target. The mass of the electrode deploys the filamentfrom storage and behind the electrode in such a manner that the filamentspans a distance between the launch device and the electrode positionedat a target. The mass of an electrode is generally insufficient to causeserious blunt impact trauma to a target. In one implementation, the massof an electrode is in the range of 2.0 to 3.0 grams, preferably about2.8 grams.

An electrode provides a surface area for receiving a propelling force topropel the electrode away from a launch device and toward a target.Movement of the electrode away from the launch device is limited byaerodynamic drag and resistance force (e.g., tension in the filament)that resists deploying a filament from storage and pulling the filamentbehind the electrode in flight toward a target.

A forward portion of an electrode may be oriented toward a target priorto launch. Upon launch and/or during flight from the launch devicetoward the target, the forward portion of the electrode orients towardthe target. An electrode has an aerodynamic form for maintaining theforward portion of the electrode oriented toward a target. Theaerodynamic form of an electrode provides suitable accuracy for hittingthe target.

An electrode includes a shape for receiving a propelling force to propelthe electrode toward a target. A shape of an electrode may correspond toa shape of a portion of the launch device or deployment unit thatprovides a propelling force to propel the electrode. For example, acylindrical electrode may be propelled from a cylindrical tube of adeployment unit. During a launch of an electrode by expanding gas, theelectrode may seal the tube with the body of the electrode to accomplishsuitable acceleration and muzzle velocity. A rear face of thecylindrical body may receive substantially all of the propelling force.

An electrode may include a substantially cylindrical body. Prior tolaunch, the electrode is positioned in a substantially cylindrical tubeslightly larger in diameter than the electrode. A propelling force(e.g., rapidly expanding gas) is applied to a closed end of the tube.The gas pushes against a rear portion of the body of the electrode topropel the electrode out of an open end of the tube toward a target.

An electrode includes a shape and a surface area for aerodynamic flightfor suitable accuracy of delivery of the electrode across a distancetoward a target, for example, about 15 to 35 feet from a launch deviceto a target. An electrode may rotate in-flight to provide spinstabilized flight. An electrode may maintain its pre-launch orientationtoward a target during launch, flight to, and impact with a target.

In other implementations, an electrode has a conical shape (e.g., cone,golf tee, series of axially nested cones) with the base of the conicalshape receiving the propelling force.

On impact, an electrode mechanically couples to a target. Mechanicalcoupling includes penetrating target clothing and/or tissue, resistingremoval from clothing and/or tissue, remaining in contact with a targetsurface (e.g., tissue, hair, clothing, armor), and/or resisting removalfrom the target surface. Coupling may be accomplished by piercing,lodging (e.g., hooking, grasping, entangling, adhering, gluing), and/orwrapping (e.g., encircling, covering). An electrode, according tovarious aspects of the present invention, includes structure (e.g.,hook, barb, spear, glue ampoule, tentacle, bolo) for mechanicallycoupling the electrode to a target. A structure for coupling maypenetrate a protective barrier (e.g., clothing, hair, armor) on an outersurface of a target.

In one implementation, an electrode includes a body and a spear (e.g.,pointed shaft, needle). The spear penetrates target clothing and/ortissue up to the length of the spear. The body arrests penetration. Aspear extends away from the body toward the target. The spear mayinclude one or more barbs for increasing the strength of the mechanicalcoupling of the electrode to the target. The barbs may be arranged toaccomplish suitable mechanical coupling at various lengths ofpenetration of clothing and/or tissue.

An electrode is mechanically coupled to a filament to deploy thefilament from storage and to extend the filament from the launch deviceto the target. Mechanical coupling includes coupling a filament and anelectrode with sufficient strength to retain the coupling duringmanufacture, prior to launch, during launch, after launch, duringmechanical coupling of the electrode to a target, and while delivering astimulus signal to a target. A mechanical coupling may be establishedbetween a filament and an electrode in any conventional manner (e.g.,threading the filament through a hole in the electrode and knotting thefilament to prevent unthreading, tying the filament in a knot to aportion of the electrode, gluing the filament to the electrode, joining(e.g., welding, soldering) a portion of the filament to a portion of theelectrode). Mechanical coupling may be accomplished by confining thefilament in a portion of the electrode. For example, confining a portionof the filament in an interior of the electrode. Confining may includeenclosing, holding, retaining, maintaining mechanical coupling, and/orresisting separation. Confining may be accomplished by preventing orresisting movement or deformation (e.g., stretching, twisting, bending)of the filament. As discussed below, placing the filament in an interiorand affixing a spear over the interior in one implementation confinesthe filament to the interior.

An electrode facilitates electrical coupling of the launch device andthe target. Electrical coupling generally includes a region or volume oftarget tissue associated with the electrode (e.g., a respective regionfor each electrode when more than one electrode is used). According tovarious aspects of the present invention, one or more structures of theelectrode accomplish lower current density in the region or volumecompared to prior art electrodes.

For each electrode, electrical coupling may include placing theelectrode in contact with target tissue (e.g. touching, inserting)and/or ionizing air in one or more gaps between the launch device, thedeployment unit, the filament, the electrode, and target tissue. Forexample, a placement of an electrode with respect to a target thatresults in a gap of air between the electrode and the target does notelectrically couple the electrode to the target until ionization of theair in the gap. Ionization may be accomplished by a stimulus signal thatincludes, at least initially, a relatively high voltage (e.g., about25,000 volts for one or more gaps having a total length of about oneinch). After initial ionization, the electrode remains electricallycoupled to the target while the stimulus signal supplies sufficientcurrent and/or voltage to maintain ionization. Ionization may not beneeded, for instance when contact is accomplished by spreading involvingdirect conduction from a filament to the target.

In an electrode, according to various aspects of the present invention,conduction of current from the electrode is enhanced at surface tissueof the target and diminished at the tip inserted in target tissue. Theseeffects are accomplished by spreading and/or diffusing.

An electrode for use with a deployment unit and/or an electronic weapon,according to various aspects of the present invention, performs thefunctions discussed above. For example, any of electrodes 142, 143, 600,700, and 800 of FIGS. 1-8 may be launched from weapon 100 toward atarget to establish a circuit with the target to provide a stimulussignal through the target.

Electronic weapon 100 of FIG. 1 includes launch device 110 anddeployment unit 130. Launch device 110 includes user controls 112,processing circuit 114, power supply 116, and signal generator 118. Inone implementation, launch device 110 is packaged in a housing. Thehousing may include a mechanical and electrical interface for adeployment unit 130. Conventional electronic circuits, processingcircuit programming, and propulsion and mechanical technologies may beused, suitably modified, and/or supplemented as discussed herein.

A user control is operated by a user to initiate an operation of theweapon. User controls 112 may include a trigger, a manual safety, and/ora touch screen user interface operated by a user. When user controls 112are packaged separately from launch device 110, any conventional wiredor wireless communication technology may be used to link user controls112 with processing circuit 114.

A processing circuit controls many if not all of the functions of anelectronic weapon. A processing circuit may initiate a launch of one ormore electrodes responsive to a user control. A processing circuit maycontrol an operation of a signal generator to provide a stimulus signal.For example, processing circuit 114 receives a signal from user controls112 indicating user operation of the weapon to launch an electrode andprovide a stimulus signal. Processing circuit 114 provides a launchsignal 152 to deployment unit 130 to initiate launch of one or moreelectrodes. Processing circuit 114 may provide a signal to signalgenerator 118 to provide the stimulus signal to the launched electrodes.Processing circuit 114 may include a conventional microprocessor andmemory that executes instructions (e.g., processor programming) storedin memory.

A power supply provides energy to operate an electronic weapon and toprovide a stimulus signal. For example, power supply 116 provides energy(e.g., current, pulses of current) to signal generator 118 to provide astimulus signal. Power supply 116 may further provide power to operateprocessing circuit 114 and user controls 112. For hand held electronicweapons, a power supply generally includes a battery.

A signal generator provides a stimulus signal for delivery through atarget. A signal generator may reform energy provided by a power supplyto provide a stimulus signal having suitable characteristics (e.g.,ionizing voltage, charge delivery voltage, charge per pulse of current,current pulse repetition rate) to interfere with target locomotion. Asignal generator electrically couples to a filament to provide thestimulus signal through the target as discussed above. For example,signal generator 118 provides a stimulus signal to electrodes 142-143 ofdeployment unit 130 via their respective filaments 140-141. Signalgenerator 118 is electrically coupled via stimulus interface 150 tofilaments stored in deployment unit 130. The stimulus signal may consistof from 5 to 40 pulses per second, each pulse capable of ionizing air,each pulse delivering after ionization (if needed) about 80microcoulombs of charge through a human or animal target having animpedance of about 400 ohms.

A deployment unit (e.g., cartridge, magazine) receives a launch signalfrom a launch device to initiate a launch of one or more electrodes anda stimulus signal to deliver through a target. A spent deployment unitmay be replaced with an unused deployment unit after some or allelectrodes of the spent deployment unit have been launched. An unuseddeployment unit may be coupled to the launch device to enable additionalelectrodes to be launched. A deployment unit may receive, via aninterface, signals from a launch device to perform the functions of adeployment unit.

For example, deployment unit 130 may include one or more cartridges132-134. Each cartridge 132 (134) may include one or more filaments 140(141), one or more electrodes 142 (143), and one or more propellants 144(145). A deployment unit stores a filament for each electrode or groupof electrodes. Each filament mechanically couples to an electrode orgroup of electrodes as discussed herein. Via launch signal 152,processing circuit 114 initiates activation of propellant 144 (145) forone or more selected cartridges. Propellant 144 (145) propels one ormore electrodes 142 (143) toward a target. Each electrode is coupled todeploy a respective filament from storage. As each electrode fliestoward the target, each electrode deploys its respective filament outfrom its storage. Signal generator 118 provides the stimulus signalthrough the target via stimulus interface 150 and the filaments coupledto launched electrodes 142 (143).

Each propellant may serve to launch any number of electrodes. Forinstance, a deployment unit formed as a replaceable cartridge mayinclude a housing, an electrical interface, two electrodes, onepropellant for launching the two electrodes, and two filaments, one foreach electrode.

An electrode, according to various aspects of the present invention,performs one or more of the following functions in any combination:binding the filament to the electrode, deploying the filament,mechanically coupling the electrode to a target, enabling conduction ofthe stimulus current from the filament through the target, spreading acurrent density with respect to a region of target tissue, and diffusinga current into a volume of target tissue. Enabling conduction includesionizing, spreading, and/or diffusing. Enabling conduction, may includeionization of insulative material internal to one or more portions ofthe electrode. Enabling conduction may include ionization of insulativematerial external to the electrode. Insulative materials include anymaterial or substance (e.g., gas, liquid, solid, aggregation,suspension, composite, alloy, mixture) that presents, at any time ortimes, a relatively high resistance to current of the stimulus signal.

A functional block diagram of an electrode, according to various aspectsof the present invention illustrates functional and structuralcooperation. Lines shown on FIG. 2 illustrate paths by which current isconducted. Arrows on these lines show a single polarity for current flowfor clarity of description. Current of any conventional polarity orpolarities may flow in one or more directions on any of the lines shownat various times. Return path 246 may be accomplished in any mannerdiscussed above.

Electrode 142 includes binding and/or deploying structure 202; couplingand/or diffusing structure 204; and a regional spreading structure 206.Electrode 142 performs mechanical and electrical functions. Receivingand conducting the stimulus signal is herein called activation.Electrode 142 is activated via filament 140 with current to signalgenerator 118 and with current from target tissue 208 on one or morepaths through electrode 142 and one or more paths through target tissue208.

A binding deploying structure has mass, shape, and surfaces for beingattached to a filament, for being propelled, and for deploying thefilament to a target, as discussed above. Conventional mass, shape, andsurfaces may be employed. For example, a binding structure may have asubstantially cylindrical shape, an interior with surfaces that abutand/or grip a filament, and external surfaces with suitable aerodynamicproperties for efficient propulsion and accurate flight to a target. Abinding deploying structure may employ conductive, resistive, and/orinsulative material on an intended path of conduction of stimuluscurrent. A binding deploying structure may employ resistive and/orinsulative material to diminish stimulus current conduction on undesiredpaths. Conventional metal and/or plastic fabrication technologies may beused in the manufacture of a binding deploying structure as discussedherein.

For example, binding deploying structure 202 binds an end portion of afilament (e.g., an insulated wire 140) for deploying the filament inresponse to propulsion (e.g., by propellant 144). In addition, bindingdeploying structure 202 may conduct the stimulus current as discussed inTable 1.

Diffusing facilitates formation and use of at least one current path forstimulus signal current through tissue of the target, subtracting fromcurrent that would otherwise pass into target tissue through a tip ofthe electrode. As a result of diffusing, stimulus current divides amongthe at least two current paths. Diffusing reduces electric field fluxdensity in a volume of target tissue (e.g. near a tip). A structure ofconventional materials may accomplish diffusing as discussed herein.Such a structure may have any shape known in the art for inserting anelectrode into a volume of target tissue. A diffusing structure includesconductive material and may further include insulative material, forexample, to inhibit ionization from undesired surfaces and/or locationsof the diffusing structure.

A coupling diffusing structure accomplishes mechanical coupling of theelectrode to the target (e.g., target's tissue, target's clothing) asdiscussed above. A coupling diffusing structure has a shape suitable forthe mechanical coupling method(s) being implemented as well as shape andmaterial suitable for electrical coupling (e.g., forming ionized paths,conducting stimulus signal current) and diffusing current density.Mechanical coupling may be accomplished with piercing. When piercing andlodging are used for coupling, the coupling diffusing structure may haveone or more shafts of small diameter compared to the length of theshaft. Each shaft may include a tip sufficient to pierce material and/ortissue at the target. Lodging may be accomplished with any conventionalirregularity of the surface of the shaft at the tip, spaced away fromthe tip, or continuing from the tip. Mechanical coupling may beaccomplished without piercing. When coupling includes lodging and/orwrapping the coupling diffusing structure may have a relatively bluntsurface for colliding with material and/or tissue at the target. Forexample, the blunt surface may have a relatively large adhering surfacecompared to a spear. A blunt surface may be long, as implemented with atentacle deployed on impact that adheres to the target and/or adheres toitself.

For example, coupling diffusing structure 204 may include a spearcomprising a shaft formed or joined to binding deploying structure 202.The shaft may terminate with a sharp tip. In addition, couplingdiffusing structure 204 may conduct the stimulus current as discussed inTable 1.

Spreading facilitates formation and use of at least one current path forstimulus signal current through skin of the target, subtracting fromcurrent that would otherwise enter target tissue through a tip of theelectrode. As a result of spreading, stimulus current divides among theat least two current paths. Spreading reduces electric field fluxdensity in a volume of target tissue (e.g. near a tip). A structure ofconventional materials may accomplish spreading as discussed herein.Such a structure may have any shape known in the art for spreading anelectric field across a region or throughout a volume. A spreadingstructure includes conductive material and may further includeinsulative material, for example, to inhibit ionization from undesiredsurfaces and/or locations of the spreading structure.

A regional spreading structure improves the conductivity of a surface ina region near a point of impact of the electrode and the target. Aregional spreading structure may dispense a conductive substance (e.g.,liquid, gel, suspension, aggregate, powdered solid) to spread thecurrent density of the stimulus signal into the region. The region maybe immediately adjacent to a point of impact. The region may surround(e.g., encompass) the point of impact. The region may be spaced apartfrom the electrode and/or point of impact, for instance, separated fromthe electrode by a second interstitial region where conductivity is notimproved by the regional spreading structure. An electrode may producemore than one point of impact. The region may be centrally locatedbetween points of impact. The region may have an area larger than anarea that is subject to contact by blunt impact of the electrode.

For example, regional spreading structure 206 may comprise a containerthat supplies conductive material onto or into the region. The containermay conduct the stimulus current into the conductive material. Becausespreading may be a consequence of the conductivity of the materialdispensed, the container may spread the stimulus current density withoutsupplying the stimulus current to the material dispensed. See Table 1for illustrative implementations.

The seven configurations of Table 1 provide guidance for construction ofat least seven electrodes. The techniques illustrated by theseconfigurations may be combined in any practical manner for constructionof additional electrodes. Current division may be described as a ratioof the currents 242 and 244. Zero or more of the paths 212 through 244may require ionization to become effective. Zero or more of the pathsmay be constructed to include a resistance. A suitable ratio may beaccomplished by adjusting ionization (e.g., quantity of gaps, gaplength(s)) and/or resistance of one or more paths 212 through 244. Forexample, the structures of electrode 142 in one implementation enables arelatively low voltage of the stimulus signal to effect path 214/242, arelatively higher voltage to effect path 216/242 or 216/244, and a stillhigher voltage to effect path 218/244.

Current 242 may be expressed as a percentage of total current I (e.g.,{100*i (242)}/{i (242)+i (244)}). A non-zero percentage providesbeneficial reduction of electric field strength at an electrode tipinserted in target tissue. According to various aspects of the presentinvention, greater percentages are even more beneficial. In oneimplementation, the percentage is in the range of from about 50% toabout 99%. In other implementations, the percentage is in the range offrom about 20% to about 80% due to limitations of structural strengthand economics of material costs and manufacturing.

TABLE 1 Activation Sequence Accomplishing Division Of CurrentConfiguration Through Target 208 (via 242 and 244) 1 Filament 140activates (216) binding deploying structure 202 which activates (224)coupling diffusing structure 204 for current 244. Coupling diffusingstructure 204 activates (226) regional spreading structure 206 forcurrent 242. 2 Filament 140 activates (216) binding deploying structure202 which activates (222) regional spreading structure 206 for current242. Regional spreading structure 206 activates (228) coupling diffusingstructure 204 for current 244. 3 Filament 140 activates (216) bindingdeploying structure 202 which activates (224, 222) both couplingdiffusing structure 204 for current 244 and regional spreading structure206 for current 242. 4 Filament 140 activates (218) coupling diffusingstructure 204 for current 244. Coupling diffusing structure 204activates (226) regional spreading structure 206 for current 242. 5Filament 140 activates (218) coupling diffusing structure 204 forcurrent 244. Coupling diffusing structure 204 activates (225) bindingdeploying structure 202 which activates (222) regional spreadingstructure 206 for current 242. 6 Filament 140 activates (214) regionalspreading structure 206 for current 242. Regional spreading structure206 activates (228) coupling diffusing structure 204 for current 244. 7Filament 140 activates (214) regional spreading structure 206 forcurrent 242. Regional spreading structure 206 activates (223) bindingdeploying structure 202 which activates (224) coupling diffusingstructure 204 for current 244.

In various implementations according to Table 1, structures 202-206 maybe implemented using conventional manufacturing technologies (e.g.,molding, casting, machining, joining, crimping, staking, fastening,adhering, coating, over molding, abutting, assembling) as needed tosupport conductivity for the desired one or more paths 212-244. Currentpaths shown schematically on FIG. 2 adjacent to a gap may be subsumed instructures adjacent to the gap.

When more than one path of paths 212-244 is formed, stimulus currentdivides among the formed paths (an inclusive OR of the paths 212-244).Due to changes in the environment of the electrode (e.g., movement ofthe electrode and/or the target with respect to the other), changingsignal generator output voltage V_(A), changes in the conductivity oftarget tissue), one or more of paths 212-244 may form, decay, and/orreform over time (e.g., during a series of pulses of stimulus current).

An electrode according to various aspects of the present invention mayhave one or more binding deploying structures 202 (e.g., more than onefilament for redundancy, one for each of several stimulus signals), oneor more coupling diffusing structures 204 (e.g., increased lodgingcapability with decreased depth of piercing tissue), and/or one or moreregional spreading structures 206 (e.g., plural spreading structuressymmetrically arranged around the shaft of one spear, one or morespreading structures for each of several coupling diffusing structures).

In operation with one of each structure as shown, a voltage V_(A) isimpressed by signal generator 118 across a filament 140 (212) and areturn path 246. The return path may be through earth or through asecond electrode (not shown) analogous to electrode 140. Current (I) mayflow through target 208 by any one or more paths 242-244.

An example impact of one implementation of electrode 142 is shown incross section in FIG. 3. Electrode 142 has a central axis 316. As shown,binding deploying structure 202 maintains a rigid arrangement of itself,an end portion of filament 140 and an end portion of coupling diffusingstructure 204. Filament 140 comprises a coaxially insulated conductor212. Conductor 212 is exposed to the atmosphere near binding deployingstructure 202, coupling diffusing structure 204, and regional spreadingstructure 206. As shown, electrode 142 has made impact with target 208by piercing a surface of the target, namely, clothing 302 that remains adistance 322 (exaggerated merely for clarity of presentation) away fromskin 304 of the target. Regional spreading structure 206 has deformed onimpact with the target.

Binding deploying structure 202 includes a cylindrical body 310 and afront face 313 both symmetric about axis 316. Body 310 retains filament140 and coupling diffusing structure 204 by friction. Body 310 may beconductive (as shown).

Coupling diffusing structure 204 includes a shaft 311, a tip 314, and abarb 312. Shaft 311 has a longitudinal axis aligned with axis 316.Coupling diffusing structure 204 is conductive at voltages above anactivation voltage.

Coupling diffusing structure 204 may be activated by any one or more ofcurrents 216 and 219 through body 310, and 218 from filament 140 at alocale a distance 315 from tip 314. Tip 314 may be activated via anycurrent in shaft 311, provided sufficient activation voltage isavailable.

In one implementation, activation of tip 314 involves a series circuitcomprising intrinsic resistance of shaft 311 and/or one or more gaps(e.g., series 332, 334, and 336) each gap requiring ionization forcurrent to freely flow. Ionization occurs internally to shaft 311.Assuming sufficient activation voltage to activate shaft 311 to a localenear skin 304, a portion 244 of current in coupling diffusing structure204 enters target tissue. An activation voltage of tip 314 is higherthan the activation voltage to produce current 244 due to additionallength of intrinsic resistance and/or additional gaps (not shown) in thematerial of shaft 311, gaps 332, 334, and 336 being illustrative of aprinciple of activation. Consequently, a portion of current 228 incoupling diffusing structure 204 is inhibited from flowing through tip314 by intrinsic resistance and/or gaps and enters target tissue at alocale different from tip 314 (e.g., current 244 near skin 304). Current344 flows in a volume of target tissue 208. Current 344 and anassociated electric field flux density at tip 314 are consequently lessin comparison to a shaft, barb, and tip formed of highly conductingmaterial (e.g., stainless steel as in the prior art).

Regional spreading structure 206 comprises a container 306 formed ofinsulative material and a conductive gel 308. On impact, the containerdeforms, ruptures, and dispenses the gel away from coupling diffusingstructure 204 and away from axis 316 of electrode 142. The gel makesconductive contact with the surface 302 up to a distance 307 fromcoupling diffusing structure 204. In one implementation, distance 307 isgreater than a radius of electrode 142 from axis 316. Gel 308 may beactivated by any one or more of currents 222, 214, and 216 at anactivation voltage that depends at least in part on the conductive orinsulative properties of the materials of binding deploying structure202, container 306, and shaft 311. Current 242 enters skin 304 adistance 309 away from coupling diffusing structure 204. Currents 342flow in a volume of target tissue 208.

In another implementation, a relatively low viscosity conductivematerial (e.g., liquid) may substitute for conductive gel 308 to permitflow through clothing 302. Conductive gel 308 may cause clothing 302 toadhere to skin 304 by virtue of wetting, surface tension, electrostaticattraction, and/or chemical adhesion.

In operation after impact, electrode 142 inhibits current 344 throughtip 314 by spreading and diffusing to enable currents 242, 342, and 244not through tip 314. Currents 342 and 244 exist in response to electricfield flux density in the locale of each current. The structures ofelectrode 142 diffuse and spread the electric field flux density thatwould otherwise occur at tip 314 by diffusing current through any localeof shaft 311 in contact with target tissue (the locale at current 244for example), by inhibiting activation of tip 314 through use ofmaterials in shaft 311 and/or tip 314 that are not highly conductive,and/or by enabling current flow 342 at a distance from the electrodethrough use of regional spreading.

Activation of shaft 311 and current 244 occurs at a voltage lower thanan activation voltage of tip 314. Current 244 is representative ofcurrents from shaft 311 at any locale where shaft 311 is in contact withtarget tissue 208. Other currents from shaft 311 (not shown) may beactivated at respective activation voltages that are less than theactivation voltage of tip 314. In one implementation, such activationvoltages are inversely proportional to distance of the respective localefrom tip 314. Proportionality may be linear or nonlinear as a result ofchoice of insulative materials and manufacturing techniques used to formand assemble structure 204.

Activation of regional spreading structure 206 occurs at a voltage lowerthan an activation voltage of tip 314. Activation of regional spreadingstructure 206 may occur at a voltage lower than an activation voltageassociated with current 244 (representing currents from shaft 311 not attip 314). As a result, at preferred operating voltages for electrode142, current 342 may have a magnitude greater than current 244(representing currents from shaft 311 not at tip 314); and/or current342 may have a magnitude greater than a sum of magnitudes of currents244 and 344.

An electronic weapon 100, according to various aspects of the presentinvention, may launch two electrodes each of the type discussed hereinwith reference to electrode 142, where one electrode serves in thereturn path, as discussed above. For example, electronic weapon 100 ofFIG. 4 is shown immediately after a user initiated launch of twoelectrodes from a deployment unit. Electronic weapon 100 includes ahand-held launch device 110 that receives and operates onefield-replaceable cartridge 130 as a type of deployment unit. Launchdevice 110 houses a power supply (having a replaceable battery), aprocessing circuit, and a signal generator as discussed above. Launchdevice 110 may be of the type known as a model X26 electronic controldevice marketed by TASER International, Inc. Cartridge 130 includes aplurality 402 of tethered electrodes including electrodes 142 and 143.Upon operation of trigger 401, electrodes 142 and 143 are propelled fromcartridge 130 generally in direction of flight “A” toward a target (notshown). As electrodes 142 and 143 fly toward the target, electrodes 142and 143 deploy behind them filaments 140 and 441 respectively. Whenelectrodes 142 and 143 are positioned in or near the target, filaments140 and 441 extend from cartridge 130 to electrodes 142 and 143respectively. The signal generator provides a stimulus signal throughthe circuit formed by filament 140, electrode 142, target tissue,electrode 143, and filament 441. Electrodes 142 and 143 mechanically andelectrically couple to tissue of the target as discussed above.

A deployment unit may substantially simultaneously deploy a plurality ofelectrodes. For example, deployment unit 130 of FIG. 5 includes theexterior dimensions, features, and operational functions, of aconventional cartridge of the type used with model M26 and X26electronic control devices marketed by TASER International, Inc. FIG. 5is drawn to scale with the angle formed by the launch tubes being 8degrees. For deployment unit 130, two electrodes are simultaneouslypropelled from respective cylindrical launch tubes (e.g., bore, chamber)in a housing of the deployment unit. For example, deployment unit 130includes housing 502, cover 508, filament storage (not shown), bores 504and 506, propellant system 144, 145 comprising several components, andtethered electrodes 142 and 143. Each tethered electrode 142 (143) ismechanically coupled to a respective filament (one shown) 141, to deploythe filament with the electrode. Spaces for filament storage are locatedon both sides of the plane of the bores of the housing, so that in thecross-section view of FIG. 5, one storage space is removed by crosssection and the other is hidden. In use, the propellant explosivelyprovides a volume of gas that pushes each electrode 142 (143) from therespective bore 504 (506). Acceleration, muzzle velocity, flightdynamics, and accuracy of hitting the target are affected by the fit ofthe body as it leaves the bore. Any diameter along the length of thebody that exceeds a limit interferes for a period of time unnecessarilywith propelling the body from the bore.

Portions of an electrode, as discussed above, may be formed, accordingto various aspects of the present invention, of materials that are nothighly conductive. These materials are discussed above as resistiveand/or insulative. The structure of these materials may be uniformthrough a volume or nonuniform. When uniform, electrical activation maybe in accordance with a resistance per unit length and one or morelengths of conduction (path lengths) needed to accomplish suitableactivation. Nonuniformity may be accomplished by varying the blend ofconstituents of the material when molding the desired structure, or byarranging materials of different properties in series assembly.Nonuniformity may cause resistance to increase away from the target orto any desired nonlinear extent. Conductive and/or resistive materialsmay be combined with insulative materials in any conventional fashion.

Insulative materials include nonconductors. When exposed to ionizationvoltages, portions of insulative materials along paths of ionization mayreform (e.g., wear, deform, mobilize, melt, vaporize, temper, congeal,crystallize, stratify, reconstitute) into resistive materials, voids,and/or pockets of component materials (e.g., liquids or gases).Reformation may change a magnitude of voltage needed for a desiredactivation. Insulative materials may comprise plastic, nylon,fiberglass, or ceramic. Insulative coatings include lacquer, black zinc,a dielectric film, a non-conductive passivation layer, a polyp-xylylenepolymer (e.g., Parylene), polytetrafluoroethylene (e.g., Teflon), athermoplastic polyamide (e.g., Zytel). Conventional insulativetechnologies may be used.

Insulative materials of a type herein called composite materials, mayinclude separated conductors. Conventional composite materials aremanufactured and used for molding and overmolding. For example, acomposite material may be formed from a liquid resin, plastic, orthermoplastic as a host material with solid fibers, spheres, ellipsoids,powder, or other particles as filler mixed into the host before the hostcures to a solid. Host material may be plastic, nylon, PEEK(polyetheretherkeytone), thermoplastic elastomer (e.g., thermoplasticpolyurethane (TPU)), SBS poly(styrene-butadiene-styrene) rubber.Particles of conductive (e.g., metal, stainless steel, tungsten) orresistive (e.g., carbon) material may be used as filler. Particleshaving a coating of conductive or resistive material may be used asfiller. For example, insulative material of the type marketed by RTP Co.as thermoplastic polyurethane elastomer (TPUR/TPU) comprisingnickel-coated carbon fiber may be used. Spheres or powder may have adiameter of from about 3 to about 11 microns. Fibers may have a similardiameter and a length of from about 5 to about 7 millimeters. Filler tohost by weight may be from about 5% to about 40% to assure separation(nonoverlap) of particles. Composition may result in activation voltagesof from about 50 volts to about 6000 volts for components of electrodes142.

In one exemplary implementation in accordance with the functionsdiscussed above with reference to FIGS. 1-5, binding deploying structure202 is implemented as a body, coupling diffusing structure 204 isimplemented as a spear having a shaft and a tip, and regional spreadingstructure 206 is implemented as a container that contains an amorphousconductor.

The body and spear may be of dissimilar materials. Forming the bodycomprising a material with significant ductility (e.g., a zinc alloy)may facilitate binding of the filament and/or assembling of the filamentand the body. Forming the spear comprising a material with significanthardness (e.g., a stainless steel alloy) may facilitate forming a tipfor piercing and a barb for lodging.

A body may perform binding and deploying as discussed above. A body mayhave any size and shape known in the art for suitably binding a filamentand deploying a filament (e.g., substantially spherical, substantiallycylindrical, having an axis of symmetry in the direction of flight,bullet shaped, tear drop shaped, substantially conical, golf teeshaped). In various implementations, a body may be conductive,resistive, or insulative. If insulative, the body may comprise compositematerial and/or be coated with insulative material.

A spear may perform mechanical coupling and diffusing as discussedabove. A spear may have any size and shape known in the art for suitablypiercing material and/or tissue of a target, lodging in material and/ortissue of a target, and forming an ionized path from the tip of thespear to target tissue. In various implementations, a spear may beresistive or insulative. When insulative, the body may comprisescomposite material and/or be coated with insulative material. Activationand use of a shaft and/or tip may reform paths through the insulativematerial.

A container includes any structure that maintains the shape of anamorphous substance. A container may be formed to rupture on impact witha target by being thin, brittle, scored, and/or pre-stressed. Rupturemay be designed to dispense the substance uniformly or in jets.Conventional materials may be used, such as those adapted for sportsinvolving paint balls. For example, a thin brittle plastic (e.g.,polystyrene) may be used.

The container may be formed with locales where activation is desired.For example, activation by current 226 in FIG. 2 may be encouraged by anelectrical weakness of the container near shaft 311.

An amorphous conductor includes any substance with suitable electricalproperties to serve as a conductor for the stimulus signal (e.g.,ionization current, muscle stimulus current). The amorphous conductormay comprise a liquid, paste, gum, or gel. For example, a hydrogel ofthe type used for medical testing electrodes may be used. A gel marketedby Ludlow Technical Products (e.g., GRG73P) may be used.

According to various aspects of the present invention, a ratio of thecurrent delivered through target tissue via a coupling diffusingstructure to the current delivered through target tissue via a regionalspreading structure is designed to account for expected target impactand expected reformation of materials of the electrode. The ratio maydecrease over time responsive to reformation when materials of thecoupling spreading structure are more subject to reformation than otherstructures such as the regional spreading structure.

A launcher with signal generating capabilities that suitably adjust toreformation of electrode materials may be used. The voltage applied toan electrode may be adjusted to control (e.g., regulate, mitigate,encourage, limit, respond to) reformation of the material of the bodyand/or the spear. A voltage applied (V_(A)) may assure sufficient chargeis delivered through target tissue. For example, electrodes as discussedhere may be used with a launcher as described in any of the following:U.S. Pat. No. 7,457,096, publications U.S.-2008/158769-A1, and/orU.S.-2008-0259520-A1, each incorporated by reference in its entirety forany purpose.

A regional spreading structure may form a region of relatively higherconductivity as a consequence of impact with the target. Such a region,according to various aspects of the present invention, may have an arealarger than an area of the body (e.g. a front, face, contact surface)that is in contact with the regional spreading structure. In addition, aregional spreading structure may absorb and/or dissipate kinetic energyof the electrode to reduce blunt impact trauma to tissue of the target.

In one implementation, the regional spreading structure is implementedas one or more containers of conductive material. A voltage of thestimulus signal may ionize air in a gap between the conductor of afilament and the conductive portion of a regional spreading structure toestablish an electrical coupling for a duration of ionization in thegap. Due to the small dimensions of the gap between the conductor of thefilament and a regional spreading structure, a relatively low voltage(e.g., 200V-400V) stimulus signal may activate the regional spreadingstructure, traversing any intervening material and/or ionizingrelatively short air gaps.

A spear may include an insulator. An insulator may insulate all or anyportion of a spear. A spear may be partially or entirely formed of amaterial that electrically insulates. An insulator may be of a type(e.g., thickness, material, structure) that electrically insulates thespear against a current having a voltage below a threshold, but fails toinsulate the spear against a current having a voltage above thethreshold. An insulator may be formed (e.g., shaped, applied,positioned, removed, partially removed, cut) to establish a likelylocation on the spear where the insulator may fail to insulate against acurrent having a voltage above a threshold. An insulator may bepositioned on or near a spear relative to a regional spreadingstructure. An insulator may define a series of gaps between conductorsof the spear or conductive portions of the spear. The gaps may act asswitches operative to conduct in response to the applied voltage of thestimulus signal.

A regional spreading structure may include an insulator. An insulatormay insulate all or any portion of a regional spreading structure. Aregional spreading structure may be partially formed of a material thatelectrically insulates. An insulator may be of a type (e.g., thickness,material, structure) that electrically insulates the regional spreadingstructure against a current having a voltage below a threshold, butfails to insulate the regional spreading structure against a currenthaving a voltage above the threshold. An insulator may be formed toestablish a likely location on the regional spreading structure wherethe insulator may fail to insulate against a current having a voltageabove a threshold. An insulator may be positioned on or near a regionalspreading structure relative to a spear. When the regional spreadingstructure includes a container, the container may comprise insulativematerial. By dispensing conductive material away from an insulatedinterface between the regional spreading structure and a surface of thetarget (e.g., clothing, tissue), the current spreading function of theregional spreading structure is accomplished beginning at a substantialdistance from the electrode (e.g., at a distance greater than a diameterof the spear, at a distance greater than a diameter of the body, at adistance greater than a diameter of the regional spreading structureprior to impact with the target).

A tip (e.g., point, cone, apex comprising acute angles between faces,end of a shaft of relatively small diameter) operates to pierce an outersurface (e.g., layer) of a target and/or target tissue. A tip of a spearfacilitates mechanical coupling by piercing and lodging. A tip wheninsulated may operate as a gap or switch interfering with current flow(e.g., blocking) until a threshold voltage breaks down the insulatorand/or permits ionization near the tip followed by current flow throughthe tip.

A barb operates to lodge (e.g., retain) an electrode in clothing, armor,and/or tissue of a target to retain a mechanical coupling between thebarb and the target. A barb portion of a spear resists mechanicaldecoupling (e.g. separation or removal from the target). A spear mayinclude a barb near the tip. A spear may include a plurality of barbsarranged at increasing distance from the tip. A barb may include acontinuous surface of the spear (e.g., a helical channel or ridge, ascrew thread or channel, a surface having an undulation that increasesfriction between the barb and the target.

A path may include an electrical coupling established through physicalcontact of conductors and/or ionization across one or more gaps betweenconductors. A gap may include insulation of the electrode, air,clothing, armor, skin, fur, hair, and/or target poorly conductingportions of tissue.

Electrode 142 may include a shaft having a tip and one or more barbs notlocated at the tip. Such a barb or barbs may include a surface forretaining the electrode in the target. Such a surface may providemechanical coupling and may further provide electrical coupling of theshaft (or a locale of the shaft) and target tissue adjacent to the shaft(adjacent to the locale of the shaft).

For example, an electrode may include a spear 600, shown in part in FIG.6. Spear 600 includes shaft 604 and tip 606. A longitudinal axis 602passes through a center of shaft 604 and a center of tip 606. Shaft 604may be cylindrical or any conventional geometric shape in cross-sectionthrough axis 602. Shaft 604 includes a plurality 610 of barbs formedwith or assembled onto shaft 604. For example, three barbs 612, 622, and632 are shown but any suitable number of barbs may be used. Barbs may bearranged in symmetry about axis 602 and at a series of increasingdistances from tip 606. Separations may be uniform in distance.

Each barb 612 (622, 632) includes a surface 614 (624, 634) facilitatingpiercing of a surface of the target (e.g., clothing, fur, skin), forexample by sloping away from axis 602 at an obtuse angle 618 (e.g.,greater than 90 degrees). Each barb 612 (622, 632) further includes asurface 616 (626, 636) that inhibits removal of shaft 604 from thesurface of the target, for example by sloping away from axis 602 at anangle 620 of 90 degrees or less.

Barbs 610 may form a continuous surface about axis 602, for example, asa helical screw thread.

In another implementation, each barb (612) completely encircles axis 602to form a ring or cone shape.

Surfaces 614 (624, 634) and/or 616 (626, 636) may be conductive tofacilitate electrical coupling of stimulus signal current and targettissue. When shaft 604 is formed of insulative materials, one or more ofbarbs 612, 622, and 632 may be activated by ionization to a conductivesurface of each barb, for example ionization from barb to barb towardtarget tissue. The sharp point of a barb may support a suitable electricfield flux density, facilitating ionization.

Spear 600 may be formed of resistive material. In such case, a voltagefor activation of tip 606 is greater than a voltage to activate one ormore barbs 610. The resistance per unit length may be constant, increaselinearly toward tip 606, or increase in a nonlinear manner toward tip606.

Spear 600 may be formed of a composite material. Spear 600 may diffusecurrent into target tissue in any locale of shaft 604 in contact withtarget tissue. Due to division of current as discussed above, currentinto target tissue through tip 606 is inhibited by diffusion.

Diffusion may occur after insertion of a portion of spear 600 in targettissue. The barbs of spear 600 may accomplish current spreading byionization from the barb to target skin when spear 600 (or a portionthereof) is not inserted into target tissue.

Electrode 142 may include a spear formed or assembled to include rings.Each ring may facilitate coupling of the stimulus current to targettissue. Activation of a ring may require a voltage sufficient to ionizeair in a gap between a source of the current and the ring. Activation ofa series of rings by a series of ionization paths from ring to ringtoward target tissue may implement diffusion as discussed above.Ionization paths between rings are external to spear 700.

For example, electrode 700, a portion shown in cross-section in FIG. 7after impact with target tissue 714, includes body 712, a spear havingshaft 704, barb 718, and tip 716. A longitudinal axis 702 passes througha center of shaft 704. Shaft 704 may be cylindrical or any conventionalgeometric shape in cross-section through axis 702. Shaft 704 includes aplurality 720 of conductive ring formed with or assembled onto shaft704. For example, three rings 722, 724, and 726 are shown, but anysuitable number of rings may be used. Rings 720 may be arranged at aseries of increasing lengths from tip 706. Any suitable lengths may beused. Due to the lengths as shown, activation of target tissue 714occurs at a voltage less than an activation voltage of ring 726.

Shaft 704 may be formed of resistive material or composite materialprovided an insulative barrier (not shown) is included between rings720. Shaft 704 may diffuse current into target tissue in any locale ofshaft 704 in contact with target tissue.

Shaft 704 may be formed or assembled of insulative material. Shaft 704may diffuse current into target tissue in any locale of shaft 704 incontact with target tissue. Due to division of current as discussedabove, current into target tissue through tip 716 is inhibited bydiffusion.

Rings 722, 724, 726 may be formed of a conductive metal or conductivealloy of metals. When rings are formed of resilient material, they maybe snapped onto shaft 704. Rings may be formed of composite materialthat includes conductive material or formed of material that is treatedto include a conductive surface.

In operation, body 712 of electrode 700 may activate the series of rings722, 724 by supporting ionization on paths 732 and 734. Ionization ofpath 736 accomplishes spreading as discussed above as current entersskin 714 at a distance 746 from shaft 704. Path 736 may form as a conedue to the circular symmetry of ring 736.

Electrode 142 may include a body having an insulative coating, a shaftcomprising conductive and insulative materials further comprising aninsulative coating, a tip formed from the shaft, and a regionalspreading structure comprising a torus shaped conductive material. Onimpact of the electrode and a surface of the target, the regionalspreading structure deforms to provide a film between the body and thesurface of the target to promote conductivity of stimulus current intotarget tissue at a distance from the tip. The insulative coatingsinhibit ionization and currents between electrodes in a cartridge priorto deployment. The insulative coating on the shaft may improveresiliency, resistance to breakage, and/or sheer strength of the shaft.The regional spreading structure may collapse to form a film and/orrupture an outer surface to expose and/or dispense a film of conductivematerial. The outer surface may be provided by a container formed ofinsulative material. Voids in the container may facilitate activation ofthe conductive film and exit of current from the film both at suitablelocations with respect to the filament, body, and shaft.

Electrode 142 may employ a spreading structure abutting a face of a bodyand/or a diffusing structure extending in front of a face of a body. Bylocating the spreading structure abutting the face, impact with thetarget may cause deforming and/or dispensing to facilitate spreading. Byextending a diffusing structure in front of a face, insertion of thediffusing structure may be arrested by the face.

For example, electrode 800, shown in FIG. 8, includes body 804 and spear805. Body 804 retains filament 802 and shaft 808 in any manner asdiscussed above. Spear 805 includes shaft 808, tip 810, and barb 812.Electrode 800 has a longitudinal axis through a center of body 804 and acenter of shaft 808. Shaft 808 supports regional spreading structure852, shaped as a torus and located against front face 816.

Body 804 may be formed of a conductor (e.g., a conductor (e.g., metal,stainless steel, brass, aluminum, zinc alloy. An insulative coating 842may be used to inhibit ionization between electrodes prior todeployment. For the same reason, barb 812, tip 810 and a portion ofshaft 808 extending from tip 810 to forward face 816 of body 804 may becovered with an insulative coating 862. The insulative coating may beformed of a conventional material (e.g., paint, Parylene, anodize, blackzinc, oxide, powder coat, plastic). Insulative materials 862 and 842 mayoverlap or be coextensive. Ionization and reformation of the insulativecoatings 842 and/or 862 may be intended and accomplished with suitableactivation voltage.

Insulative material 862 may accomplish electrical insulating andstructural strengthening purposes. For example, when material of shaft808 is brittle, a silicone envelope may be overmolded on spear 805. Theenvelope acts as an insulative coating 862. The envelope also acts tomaintain the electrical properties of shaft 808, in spite of, forinstance, possible fracture on impact with target. Silicone provides aresilient support to shaft 808 inhibiting fracture and maintainingfractured portions proximate for conduction of the stimulus signal withionization.

Body 804 may be formed of an insulative material (e.g., plastic, ABS,polycarbonate, nylon, high density plastic) when currents through body804 are not needed for activation of target tissue.

Body 804 may be formed of composite material. (e.g., resin basedmaterial with conductive filler). The body may exhibit an activationvoltage for forming a path for continued current flow and/or anactivation voltage for stimulating tissue of the target. Activation foreither purpose may be associated with an initial voltage (e.g.,threshold, breakdown, set-up, reformation) below which currentsufficient for the purpose is not conducted through the body and afterwhich maintaining the initial voltage is not required. As examples, body804 may be formed and/or covered to operate with an initial voltage foractivation of forming a path to target tissue in the range of about 100volts to about 25,000 volts. Body 804 may be formed and/or covered tooperate with an initial voltage for activation of stimulating tissue inthe range of about 100 volts to about 5,000 volts. Meeting or exceedingan activation voltage and/or conducting ionization and/or stimulationcurrent may reform a material of the body. Reformation may limit theuseful life of the body for the intended purpose. Body 804 may bedesigned to operate for a time limit that corresponds to a reasonabletime for escape from or arrest of the target human or animal (e.g., 60seconds).

Spear 805 may be formed of a material the same (e.g., integral with) ordifferent from body 804.

Spear 805 may be formed of a composite material (e.g., a resin basedmaterial with conductive filler). The spear may exhibit an activationvoltage for forming a path for continued current flow and/or anactivation voltage for stimulating tissue of the target. Activation foreither purpose may be associated with an initial voltage (e.g.,threshold, breakdown, set-up, reformation) below which currentsufficient for the purpose is not conducted through the body and afterwhich maintaining the initial voltage is not required. As examples,spear 805 may be formed and/or covered to operate with an initialvoltage for activation of forming a path to target tissue in the rangeof about 100 volts to about 25,000 volts. Spear 805 may be formed and/orcovered to operate with an initial voltage for activation of stimulatingtissue in the range of about 100 volts to about 5,000 volts. Meeting orexceeding an activation voltage and/or conducting ionization and/orstimulation current may reform a material of the spear. Reformation maylimit the useful life of the spear for the intended purpose. Spear 805may be designed to operate for a time limit that corresponds to areasonable time for escape from or arrest of the target human or animal(e.g., 60 seconds).

Regional spreading structure 852 may include a conductive material 854with or without an enclosing material. The conductive material may begelatinous or liquid.

For activation to ionize and/or to stimulate, the current path fromfilament 802 to body 804 to dispensed gel 854 (e.g., dispensed like 308)is preferred. If such activation is not practical (e.g., excessivedistance 322, highly insulative clothing), then for activation to ionizeand/or stimulate, the current path from filament 802 to body 804 toshaft 808 may support activation of target tissue.

In operation of electrode 800, activation of target tissue may proceedin one or more paths analogous to paths discussed above with referenceto FIGS. 2 and 3. Because tip 810 is insulated and because additionalionization paths exist in series with tip 810 due to the particle toparticle distances in the composite material of shaft 808, an activationvoltage of the regional spreading structure 852 is less than anactivation voltage of tip 810. In addition, shaft 808 promotes by loweractivation voltages the activation of target tissue from shaft 808 nearthe skin of the target as opposed to tip 810.

EXAMPLES OF THE INVENTION

First, a deployment unit in operation provides a current from a signalgenerator (not part of the deployment unit) through tissue of a target.The current inhibits voluntary movement by the target. The deploymentunit includes a housing, an interface, a filament, an electrode, apropellant, a binding deploying structure, and a coupling structure. Theinterface couples the housing to the signal generator so that theinterface receives the current. The filament is stored in the housinguntil deployment of the filament. The filament is coupled to theinterface for receiving the current. The filament conducts the currentto the electrode. The electrode is stored in the housing untildeployment of the electrode. The propellant, in the housing, inoperation propels the electrode away from the housing to deploy thefilament toward the target. The electrode includes a binding deployingstructure and a coupling structure. The binding deploying structure ismechanically coupled to the filament to deploy the filament from thehousing. The coupling structure includes a shaft and a tip. The couplingstructure is mechanically coupled to the binding deploying structure.The shaft has a longitudinal axis. The tip is for piercing the target.The shaft includes a locale (e.g., surface). A portion of the shaftalong the axis separates the locale from the tip. The locale couples theelectrode to the target.

Second, a deployment unit in operation provides a current from a signalgenerator (not part of the deployment unit) through tissue of a target.The current inhibits voluntary movement by the target. The deploymentunit includes a housing, an interface, a filament, an electrode, apropellant, a binding deploying structure, and a coupling structure. Theinterface couples the housing to the signal generator so that theinterface receives the current. The filament is stored in the housinguntil deployment of the filament. The filament is coupled to theinterface for receiving the current. The filament conducts the currentto the electrode. The electrode is stored in the housing untildeployment of the electrode. The propellant, in the housing, inoperation propels the electrode away from the housing to deploy thefilament toward the target. The electrode includes a binding deployingstructure and a coupling diffusing structure. The binding deployingstructure is mechanically coupled to the filament to deploy the filamentfrom the housing. The coupling diffusing structure includes a shaft anda tip. The coupling diffusing structure is mechanically coupled to thebinding deploying structure. The shaft has a longitudinal axis. The tipis for piercing the target. The shaft includes a surface. A portion ofthe shaft along the axis separates the surface from the tip. The surfaceelectrically couples the current through the target.

Third, a deployment unit in operation provides a current from a signalgenerator (not part of the deployment unit) through tissue of a target.The current inhibits voluntary movement by the target. The deploymentunit includes a housing, an interface, a filament, an electrode, apropellant, a binding deploying structure, and a coupling structure. Theinterface couples the housing to the signal generator so that theinterface receives the current. The filament is stored in the housinguntil deployment of the filament. The filament is coupled to theinterface for receiving the current. The filament conducts the currentto the electrode. The electrode is stored in the housing untildeployment of the electrode. The propellant, in the housing, inoperation propels the electrode away from the housing to deploy thefilament toward the target. The electrode includes a binding deployingstructure and a coupling diffusing structure. The binding deployingstructure is mechanically coupled to the filament to deploy the filamentfrom the housing. The coupling diffusing structure includes a shaft anda tip. The coupling diffusing structure is mechanically coupled to thebinding deploying structure. The shaft includes a plurality ofconductors spaced apart from the tip that cooperate to form a seriescircuit for the current through the target.

Fourth, a deployment unit in operation provides a current from a signalgenerator (not part of the deployment unit) through tissue of a target.The current inhibits voluntary movement by the target. The deploymentunit includes a housing, an interface, a filament, an electrode, apropellant, a binding deploying structure, and a coupling structure. Theinterface couples the housing to the signal generator so that theinterface receives the current. The filament is stored in the housinguntil deployment of the filament. The filament is coupled to theinterface for receiving the current. The filament conducts the currentto the electrode. The electrode is stored in the housing untildeployment of the electrode. The propellant, in the housing, inoperation propels the electrode away from the housing to deploy thefilament toward the target. The electrode includes a binding deployingstructure, and a coupling diffusing structure. The binding deployingstructure is mechanically coupled to the filament to deploy the filamentfrom the housing. The coupling diffusing structure is mechanicallycoupled to the binding deploying structure. The coupling structureincludes a tip. The coupling diffusing structure is capable of couplingthe electrode to the target. Further, the coupling diffusing structureis capable of inhibiting a portion of the current from flowing into thetarget through the tip by enabling the portion of the current to flowout of the coupling diffusing structure and into the target at a firstdistance away from the tip.

Fifth, a deployment unit in operation provides a current from a signalgenerator (not part of the deployment unit) through tissue of a target.The current inhibits voluntary movement by the target. The deploymentunit includes a housing, an interface, a filament, an electrode, and apropellant. The interface couples the housing to the signal generator sothat the interface receives the current. The filament is stored in thehousing until deployment of the filament. The filament is coupled to theinterface for receiving the current. The filament conducts the currentto the electrode. The electrode is stored in the housing untildeployment of the electrode. The propellant, in the housing, inoperation propels the electrode away from the housing to deploy thefilament toward the target. The electrode includes a binding deployingstructure, a coupling structure, and a regional spreading structure. Thebinding deploying structure is mechanically coupled to the filament todeploy the filament from the housing. The coupling structure ismechanically coupled to the binding deploying structure. The couplingstructure couples the electrode to the target. The regional spreadingstructure enables a portion of the current to flow into the target at afirst distance away from the coupling structure.

In one implementation, the regional spreading structure extends awayfrom a longitudinal axis of the electrode to contact the target. Thedistance from the coupling structure to the place where current flowsinto the target is greater than a distance the electrode extends awayfrom its longitudinal axis prior to impact with the target.

In another implementation, the regional spreading structure dispenses aconductive material to contact the target to a distance from an axis ofthe electrode greater than a radius of the electrode prior to impact ofthe electrode with the target.

Sixth, a deployment unit in operation provides a current from a signalgenerator (not part of the deployment unit) through tissue of a target.The current inhibits voluntary movement by the target. The deploymentunit includes a housing, an interface, a filament, an electrode, apropellant, a binding deploying structure, and a coupling structure. Theinterface couples the housing to the signal generator so that theinterface receives the current. The filament is stored in the housinguntil deployment of the filament. The filament is coupled to theinterface for receiving the current. The filament conducts the currentto the electrode. The electrode is stored in the housing untildeployment of the electrode. The propellant, in the housing, inoperation propels the electrode away from the housing to deploy thefilament toward the target. The electrode includes a binding deployingstructure, a coupling diffusing structure, and a regional spreadingstructure. The binding deploying structure is mechanically coupled tothe filament to deploy the filament from the housing. The couplingdiffusing structure is mechanically coupled to the binding deployingstructure. The coupling diffusing structure couples the electrode to thetarget. The coupling diffusing structure spreads electric field fluxdensity to tissue away from a tip of the coupling diffusing structure.The regional spreading structure spreads electric field flux densityinto a region of a surface of the target.

What is claimed is:
 1. A deployment unit for providing a current from asignal generator through tissue of a human or animal target, the currentfor inhibiting voluntary movement by the target, the deployment unitcomprising: a housing; an interface that couples the housing to thesignal generator, the interface for receiving the current; a filamentthat conducts the current, the filament stored in the housing prior todeployment, the filament coupled to the interface for receiving thecurrent; an electrode stored in the housing prior to deployment; and apropellant that in operation propels the electrode away from the housingto deploy the filament toward the target; wherein the electrodecomprises a tip that pierces the target; a first surface to lodge theelectrode in the target; and a second surface to lodge the electrode inthe target; wherein the first surface is located closer to the tip thanthe second surface is located from the tip.
 2. The deployment unit ofclaim 1 wherein: the electrode further comprises a shaft; and the tip,the first surface, and the second surface are integral with the shaft;3. The deployment unit of claim 1 wherein: the electrode furthercomprises a third surface to lodge the electrode in the target; and thefirst surface, the second surface, and the third surface are arranged incircular symmetry about an axis.
 4. The deployment unit of claim 1wherein: the first surface is part of a first barb; and the secondsurface is part of a second barb.
 5. The deployment unit of claim 4wherein: the electrode further comprises a shaft comprising a surface ofthe shaft; and the first barb and the second barb are part of anirregularity of the surface of the shaft.
 6. The deployment unit ofclaim 4 wherein: the electrode further comprises a spear comprising acontinuous surface; and the continuous surface includes the first barband the second barb.
 7. The deployment unit of claim 1 wherein theelectrode further comprises an undulation that increases frictionbetween the second surface and the target.
 8. The deployment unit ofclaim 1 wherein: the electrode comprises a shaft; and the second surfaceis assembled onto the shaft.